721164215663 has 2 divisors, whose sum is σ = 721164215664. Its totient is φ = 721164215662.

The previous prime is 721164215627. The next prime is 721164215741. The reversal of 721164215663 is 366512461127.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 721164215663 - 2²⁴ = 721147438447 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (721164215363) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 360582107831 + 360582107832.

It is an arithmetic number, because the mean of its divisors is an integer number (360582107832).

Almost surely, 2^721164215663 is an apocalyptic number.

721164215663 is a deficient number, since it is larger than the sum of its proper divisors (1).

721164215663 is an equidigital number, since it uses as much as digits as its factorization.

721164215663 is an evil number, because the sum of its binary digits is even.

The product of its digits is 362880, while the sum is 44.

The spelling of 721164215663 in words is "seven hundred twenty-one billion, one hundred sixty-four million, two hundred fifteen thousand, six hundred sixty-three".